Horizontal wellbore fracturing cluster erosion testing device, testing system and testing method

Abstract

This application relates to the field of oil and gas development equipment technology, and discloses a horizontal wellbore fracturing cluster erosion testing device, testing system, and testing method. The testing device includes an erosion tooling module, a formation backpressure simulation module, and a controllable flow distribution module. The erosion tooling module has a fluid outlet and is used to install the fracturing wellbore to be tested. One end of the fracturing wellbore is used to connect to a fracturing device that provides fracturing fluid, and the other end passes through the erosion tooling module, forming an annular cavity between the fracturing wellbore and the erosion tooling module. The wall of the fracturing wellbore has multiple perforations facing the fluid outlet. The formation backpressure simulation module is used to control the fluid outlet to discharge fluid at a preset constant flow rate. The controllable flow distribution module is connected to the other end of the fracturing wellbore and is used to adjust the bypass flow rate of the fracturing wellbore. The testing device disclosed in this application has a simple structure, guaranteed accuracy, small footprint, high flexibility, and low cost.

Description

Technical Field

[0001] This application belongs to the field of oil and gas development equipment technology, specifically relating to a horizontal wellbore fracturing cluster erosion testing device, testing system and testing method. Background Technology

[0002] Multi-cluster fracturing in horizontal wells is a key technology for developing unconventional oil and gas resources. Its core challenge lies in achieving uniform fluid and proppant injection across perforated clusters within a section to maximize reservoir stimulation volume. However, during fracturing, the erosion of perforated holes by proppant-carrying fluid alters hole size and friction, leading to an imbalance in the originally designed flow distribution. This causes some clusters to prematurely cease fluid injection, severely impacting fracturing effectiveness. Therefore, studying hole erosion patterns, proppant diversion characteristics, and control methods is crucial for optimizing fracturing design.

[0003] Unconventional fracturing commonly employs a long-segment, multi-cluster fracturing mode, with each long horizontal segment being at least 50 meters in length. This results in uneven distribution of fracturing fluid and proppant among the clusters, leading to a situation where "some clusters are strong and others are weak," which in turn results in low reliability of experimental data. Furthermore, due to the length limitation, it requires a large area, leading to high costs, and it cannot flexibly conduct field-level arbitrary single-cluster multi-pore high-volume erosion experiments. Summary of the Invention

[0004] The purpose of this application is to provide a horizontal wellbore fracturing cluster erosion testing device, testing system and testing method to solve the problems of unreliable experimental data, large site occupation, high cost and inability to flexibly carry out field-level arbitrary single cluster multi-hole large-volume erosion experiments in the existing large-section multi-cluster fracturing mode.

[0005] To achieve the above objectives, the first aspect of this application provides a horizontal wellbore fracturing cluster erosion testing device, comprising:

[0006] An erosion tooling module has a fluid outlet. The erosion tooling module is used to install a fracturing wellbore to be tested. One end of the fracturing wellbore is used to connect to a fracturing device that provides fracturing fluid, and the other end passes through the erosion tooling module. An annular cavity is formed between the fracturing wellbore and the erosion tooling module. The wall of the fracturing wellbore is provided with a plurality of perforations facing the fluid outlet.

[0007] A formation backpressure simulation module is connected to the outlet and is used to control the outlet to discharge liquid at a preset constant flow rate.

[0008] A controllable flow distribution module is used to connect to the other end of the fracturing wellbore and to adjust the bypass flow rate of the fracturing wellbore.

[0009] As a further improvement to the above technical solution:

[0010] In some embodiments, the erosion tooling module is provided with a buffer tank at the liquid outlet, and the buffer tank is connected to the erosion tooling module;

[0011] The formation backpressure simulation module is located at the outlet of the buffer tank.

[0012] In some embodiments, the formation backpressure simulation module is a mechanical valve or a fixed nozzle; and / or, the controllable flow distribution module is an electric valve, a magnetic valve, or an automatic nozzle.

[0013] In some embodiments, the erosion tooling module includes an erosion frame and sealing flanges disposed at both ends of the erosion frame;

[0014] The fracturing wellbore is used to pass through the sealing flanges at both ends of the erosion frame and to seal with the corresponding sealing flanges.

[0015] To achieve the above objectives, a second aspect of this application provides an erosion testing system, including a control device, a fracturing device, and a horizontal wellbore fracturing cluster erosion testing device according to the first aspect above.

[0016] The fracturing device is connected to the fracturing wellbore via a pipeline, and the control device is communicatively connected to the controllable flow distribution module in the fracturing device and the horizontal wellbore fracturing cluster erosion test device.

[0017] The control device is configured to coordinate the operation of the fracturing device and the controllable flow distribution module based on the position of the perforation cluster simulated in the fracturing wellbore.

[0018] As a further improvement to the above technical solution:

[0019] In some embodiments, the erosion testing system further includes a backflow recovery device;

[0020] The liquid outlet of the formation backpressure simulation module is connected to the backflow recovery device via an erosion pipeline, and the controllable flow distribution module is connected to the backflow recovery device via a bypass pipeline.

[0021] To achieve the above objectives, a third aspect of this application provides an erosion simulation testing method applied to the erosion testing system provided according to the second aspect above, the erosion simulation testing method comprising:

[0022] Prepare the fracturing wellbore to be tested and obtain the initial data of the perforation holes on the fracturing wellbore;

[0023] Install the fracturing wellbore into the erosion testing system, set the test parameters, and start the test.

[0024] After the test time reaches the preset duration, the current test is stopped, the fracturing wellbore is removed, and the erosion data of the perforation holes is obtained.

[0025] As a further improvement to the above technical solution:

[0026] In some implementations, the test parameters include three variable parameters, namely the erosion discharge rate Q1 of the formation backpressure simulation module, the sand concentration in the fracturing fluid, and the preset test duration;

[0027] The steps of installing the fracturing wellbore in the erosion testing system, setting test parameters, and starting the test include:

[0028] The fracturing wellbore is installed into the erosion tooling module and connected to the fracturing device via pipelines, and the three variable parameters are set.

[0029] The controllable flow distribution module's displacement is turned off or the controllable flow distribution module is turned on and kept at a constant displacement. Experimental tests are conducted according to the three set variable parameters, and experimental data is recorded in real time.

[0030] In some embodiments, the erosion simulation test method further includes:

[0031] Nine test schemes were designed according to a three-parameter, three-level orthogonal model. Each test scheme had three different variable parameters. The tests of the nine test schemes were completed in sequence. The perforation flow coefficient was determined based on the experimental data and the post-erosion data in each test scheme to obtain nine sets of data points. The erosion coefficient was determined by regression calculation based on the nine sets of data points obtained.

[0032] In some embodiments, installing the fracturing wellbore in the erosion testing system, setting test parameters, and starting the test includes:

[0033] The fracturing wellbore is installed into the erosion tooling module and connected to the fracturing device via pipeline. The sand concentration in the fracturing fluid, the erosion discharge rate of the formation backpressure simulation module, and the test time are set. At the same time, based on the different perforation cluster positions n, where n is the cluster number from the toe to the heel, the nth group of different injection discharge rates Qn is determined, where the injection discharge rate Qn = n * Q1. Meanwhile, the discharge rate of the controllable flow distribution module is determined to be Q2, where Q2 = Qn - Q1.

[0034] Based on the determined displacement Q2 of the controllable flow distribution module, the controllable flow distribution module is activated for testing.

[0035] Compared with existing technologies, the horizontal wellbore fracturing cluster erosion testing device, testing system, and testing method provided in this application have at least the following beneficial effects:

[0036] The horizontal wellbore fracturing cluster erosion testing device provided in this application uses an erosion tooling module to install the fracturing wellbore to be tested. During testing, the formation backpressure simulation module controls the discharge port to discharge fluid at a preset constant flow rate to simulate the extension pressure of fractures in the formation, i.e., erosion is carried out under conditions of back pressure. Different flow rates can be configured according to requirements. Furthermore, the bypass flow rate of the fracturing wellbore can be adjusted through a controllable flow distribution module to simulate different flow gradients from the toe to the heel of the fracturing wellbore, thereby realizing arbitrary single-cluster erosion testing and toe-to-heel cluster erosion testing. The horizontal wellbore fracturing cluster erosion testing device disclosed in this application has a simple structure, fewer influencing factors in the cluster erosion testing mode, and reliable experimental data. Moreover, the cluster erosion testing mode allows for the selection of any location for a single-cluster multi-hole high-flow-rate erosion experiment according to testing requirements, without the need for a large length setting, occupying little space, offering high flexibility, and low cost.

[0037] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0038] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without any inventive effort. In the drawings:

[0039] Figure 1 A schematic diagram of a horizontal wellbore fracturing cluster erosion testing device provided in this application embodiment;

[0040] Figure 2 A piping diagram of an erosion testing system that utilizes a horizontal wellbore fracturing cluster erosion testing device, provided as an embodiment of this application;

[0041] Figure 3 This is a flowchart of an erosion testing method for an erosion testing system provided in an embodiment of this application.

[0042] Explanation of reference numerals in the attached figures

[0043] 100. Erosion tooling module; 101. Liquid outlet; 102. Annular cavity; 110. Erosion frame; 120. Sealing flange; 130. Buffer tank;

[0044] 200. Formation backpressure simulation module;

[0045] 300. Controllable flow distribution module;

[0046] 400. Fracturing wellbore; 410. Perforation hole;

[0047] 500. Fracturing unit; 510. Fluid supply subsystem; 520. Sand tank system; 530. Sand mixing subsystem; 540. Fracturing pump truck unit;

[0048] 600. Backflow recovery device;

[0049] 700. Pipeline erosion;

[0050] 800. Bypass pipeline. Detailed Implementation

[0051] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0052] The present application will now be described in detail with reference to the accompanying drawings and exemplary embodiments.

[0053] It should be noted that unconventional fracturing commonly employs a long-section, multi-cluster fracturing mode, with each long horizontal section being at least 50 meters long. This leads to uneven distribution of fracturing fluid and proppant among the clusters, resulting in "some clusters being strong and others weak." According to field tests in some shale oil fields, due to reservoir heterogeneity, the average degree of balanced expansion of multiple clusters is only 61.8%. This is achieved by significantly reducing the number of perforations, artificially creating extremely high perforation friction to forcibly balance the flow rate of each cluster. However, downhole measurements show that excessive flow rate or insufficient number of perforations leads to proppant entering the perforations, causing erosion. This results in a significant increase in perforation diameter exceeding 100%, irregular shapes, and large differences between perforations. The mechanism involves mechanical wear of the casing metal substrate by the proppant, and the concentrated impact on the perforations (downstream) due to inertia, causing the perforations to gradually evolve into axially elongated elliptical or spindle shapes, and factors such as perforation phase. There is an urgent need to conduct laboratory tests on proppant distribution and perforation erosion patterns under different operating conditions to guide the optimization of fracturing processes.

[0054] Example 1:

[0055] On the one hand, please refer to Figure 1 This embodiment provides a horizontal wellbore fracturing cluster erosion testing device, and in particular, a mine-scale horizontal wellbore fracturing cluster perforation erosion simulation testing device.

[0056] The horizontal wellbore fracturing cluster erosion testing device provided in this embodiment includes an erosion fixture module 100, a formation backpressure simulation module 200, and a controllable flow distribution module 300. The erosion fixture module 100 has a liquid outlet 101 and an installation cavity along its length. The erosion fixture module 100 is used to install the fracturing wellbore 400 to be tested.

[0057] Please refer to the following: Figure 2 In this embodiment, when installing the fracturing wellbore 400, one end of the fracturing wellbore 400 is used to connect to the fracturing device 500 that provides fracturing fluid, and the other end passes through the mounting cavity of the erosion tooling module 100 and is used to connect to the bypass pipeline 800. An annular cavity 102 is formed between the fracturing wellbore 400 and the erosion tooling module 100 to simulate the actual operating conditions of the fracturing wellbore 400. The wall of the fracturing wellbore 400 is provided with multiple perforations 410 facing the fluid outlet 101. These perforations 410 are arranged axially along the fracturing wellbore 400 to simulate the perforation clusters at different positions from the heel to the toe of a horizontal well. It is understood that a new fracturing wellbore 400 needs to be replaced each time a test is conducted.

[0058] The formation backpressure simulation module 200 is connected to the outlet 101 of the erosion tooling module 100 (in this embodiment, the connection is made via the erosion pipeline 700). The formation backpressure simulation module 200 is used to control the discharge of fluid from the outlet 101 at a preset constant flow rate. The controllable flow distribution module 300 is used to connect to the other end of the fracturing wellbore 400 (i.e., the end away from the external fracturing device 500, which is connected via the bypass pipeline 800). The controllable flow distribution module 300 is used to adjust the bypass flow rate of the fracturing wellbore 400 to simulate the flow rate of perforation clusters at different locations.

[0059] During experimental testing, the formation backpressure simulation module 200 controls the outlet 101 to discharge fluid at a preset constant flow rate to simulate the extension pressure of fractures in the formation, i.e., erosion is carried out under conditions of backpressure. Different flow rates can be configured according to requirements. Furthermore, the bypass flow rate of the fracturing wellbore 400 can be adjusted by the controllable flow distribution module 300 to simulate different flow gradients from the toe to the heel of the fracturing wellbore 400, thereby realizing arbitrary single-cluster erosion tests and toe-to-heel cluster erosion tests.

[0060] Thus, the horizontal wellbore fracturing cluster erosion testing device provided in this embodiment has a simple structure, fewer influencing factors in the cluster erosion testing mode, and reliable experimental data. Furthermore, the cluster erosion testing mode allows for the selection of any location for a single-cluster, multi-pore, high-volume erosion experiment according to testing requirements, eliminating the need for large-length setups, minimizing space requirements, and offering high flexibility and low cost.

[0061] In this embodiment, the erosion tooling module 100 is equipped with a buffer tank 130 at the outlet 101, and the buffer tank 130 is connected to the erosion tooling module 100. The formation backpressure simulation module 200 is located at the outlet of the buffer tank 130, specifically connected to the outlet of the buffer tank 130 via the erosion pipeline 700. The purpose of setting up the buffer tank 130 is that the high-speed fluid (spar-carrying fracturing fluid) in the fracturing wellbore 400 enters the buffer tank 130 after passing through the perforation orifice 410. Due to the high flow rate, the erosion of the downstream pipeline by the sand-carrying fracturing fluid can be avoided.

[0062] Optionally, the diameter of the buffer tank 130 can be selected as 300±15mm to fit the current pipeline diameter.

[0063] In some embodiments, the formation backpressure simulation module 200 is a fixed nozzle. The function of the fixed nozzle is to maintain a certain pressure after the fluid passes through the orifice through a throttling principle, thereby simulating the propagation pressure of fractures in the formation, i.e., maintaining erosion under conditions of backpressure. Thus, fixed nozzles with different throttling flow rates can be configured according to requirements. Of course, a mechanical valve can also be selected as a replacement. The mechanical valve can be a butterfly valve, ball valve, plug valve, or throttle valve, etc. It should be understood that the above are only illustrative examples and are not intended to limit the scope of protection of this application.

[0064] In some embodiments, the controllable flow distribution module 300 is an automatic nozzle. The displacement of the automatic nozzle is controllable and adjustable. That is to say, by adjusting the automatic nozzle, the outlet can be set to flow out at a constant flow rate. By precisely controlling the bypass flow through the "automatic nozzle," the flow gradient from the toe to the heel can be dynamically simulated, representing an innovative combination of structure and control logic. Of course, the controllable flow distribution module 300 can also be an electric valve, a magnetic valve, etc.

[0065] In this embodiment, the erosion tooling module 100 has a T-shaped structure and includes an erosion frame 110 and sealing flanges 120 disposed at both ends of the erosion frame 110. The fracturing wellbore 400 is configured to pass through the sealing flanges 120 at both ends of the erosion frame 110 and to seal with the corresponding sealing flanges 120. The function of the sealing flanges 120 is to connect the fracturing wellbore 400 to the erosion frame 110 and to isolate the internal high-pressure fracturing fluid (fracture-carrying fracturing fluid) from the external atmosphere.

[0066] On the other hand, please see Figure 1 and Figure 2 This embodiment also provides an erosion testing system. The erosion testing system includes a control device, a fracturing device 500, and a horizontal wellbore fracturing cluster erosion testing device according to the above embodiment.

[0067] The fracturing device 500 is connected to the fracturing wellbore 400 via pipelines, and the control device is communicatively connected to the fracturing device 500 and the controllable flow distribution module 300 in the horizontal wellbore fracturing cluster erosion test device. The control device is configured to coordinate and control the operation of the fracturing device 500 and the controllable flow distribution module 300 according to the position of the perforation cluster simulated by the fracturing wellbore 400.

[0068] Understandably, in multi-cluster fracturing of horizontal wells, the erosion state of perforation clusters at different positions from the heel to the toe varies, and the injection and discharge flow rates corresponding to different cluster positions are also different. Therefore, the injection flow rate of the fracturing device 500 and the bypass flow rate of the controllable flow distribution module 300 can be controlled by the control device to simulate the erosion test of perforation clusters at any position from the toe to the heel of the fracturing wellbore 400, or to sequentially complete the erosion test of perforation clusters at all positions, thereby realizing arbitrary single-cluster erosion testing or cluster erosion testing from the toe to the heel.

[0069] The erosion testing system also includes a flowback recovery device 600; wherein, the outlet end of the formation backpressure simulation module 200 is connected to the flowback recovery device 600 via an erosion pipeline 700, and the controllable flow distribution module 300 is connected to the flowback recovery device 600 via a bypass pipeline 800. The flowback recovery device 600 is used to recover the fracturing fluid and proppant after the test. The flowback recovery device 600 can be optionally a flowback fluid recovery tank.

[0070] The fracturing unit 500 includes a fluid supply subsystem 510, a sand tank system 520, a sand mixing subsystem 530, and a fracturing pump truck unit 540. The sand mixing subsystem 530 is connected to both the fluid supply subsystem 510 and the sand tank system 520, and its outlet is connected to the fracturing pump truck unit 540. Specifically, the fluid supply subsystem 510 supplies fracturing fluid to the sand mixing system 530; the sand tank system 520 supplies proppant to the sand mixing system 530; and the sand mixing system 530 mixes the fracturing fluid and proppant to form a proppant-carrying fracturing fluid. The pumping end of the fracturing pump truck unit 540 is connected to the fracturing wellbore 400 via pipeline.

[0071] The fracturing truck unit can be an electrically driven fracturing truck, used to inject the proppant-laden fracturing fluid into the fracturing wellbore 400 according to the site-specific discharge rate, enabling high-precision stepless speed regulation. In some embodiments, the pump discharge rate adjustment accuracy is 0.1m. 3 / min, construction pressure less than or equal to 100MPa, designed discharge range 0.1m 3 / min-20 m 3 / min.

[0072] Furthermore, the erosion testing system also includes a data acquisition subsystem that communicates with the control device. The data acquisition subsystem is used to collect the pressure, flow rate, and density information of the fracturing fluid between the fracturing pump truck group 540 and the connected fracturing wellbore 400, the pressure, flow rate, and density information of the fracturing fluid upstream of the inlet end of the formation backpressure simulation module 200, and the pressure, flow rate, and density information of the fracturing fluid upstream of the inlet end of the controllable flow distribution module 300.

[0073] Specifically, the data acquisition subsystem includes a first information acquisition module, a second information acquisition module, and a third information acquisition module. Each of these modules includes a pressure gauge for collecting pressure information, a flow meter for collecting flow rate information, and a density meter for collecting fracturing fluid density. The first information acquisition module is installed on the pipeline between the fracturing pump truck unit 540 and the fracturing wellbore 400; the second information acquisition module is installed upstream of the fluid inlet of the formation backpressure simulation module 200; and the third information acquisition module is installed upstream of the fluid inlet of the controllable flow distribution module 300.

[0074] Optionally, the control device may include a PLC controller or an industrial computer.

[0075] Understandably, the pressure gauge, flow meter, and density meter are designed to collect the flow rate, pressure, and density of the main pipeline, bypass pipeline 800, and erosion pipeline 700, respectively, to support the establishment of the erosion theoretical model.

[0076] On the other hand, please refer to Figure 1 , Figure 2 and Figure 3 This embodiment provides an erosion simulation test method, which is applied to the erosion test system provided in the above embodiment.

[0077] In this embodiment, the erosion simulation test method includes the following steps:

[0078] S100: Prepare the fracturing wellbore 400 to be tested and obtain the initial data of the perforation hole 410 on the fracturing wellbore 400.

[0079] Specifically, the fracturing wellbore 400 to be tested must be replaced before each test. The initial data of the perforation orifice 410 can be obtained by three-dimensional imaging scanning with ultrasonic CT equipment, or by other measurement methods, such as measuring the diameter of the orifice and the degree of erosion.

[0080] S200: Install the fracturing wellbore 400 in the erosion testing system, set the test parameters, and start the test.

[0081] S300: After the test time reaches the preset duration, stop the current test, remove the fracturing wellbore 400, and obtain the post-erosion data of the perforation hole 410. Ultrasonic CT equipment can also be used for three-dimensional imaging scanning. By comparing the post-erosion data of the perforation hole 410 with the initial data, the diameter of the perforation hole 410 after erosion and enlargement can be obtained.

[0082] Compared with existing technologies, the technical solution provided in this embodiment also has the following advantages:

[0083] 1. By precisely controlling the bypass flow through the "automatic nozzle", the flow gradient from the toe to the heel is dynamically simulated, achieving joint innovation in structure and control logic.

[0084] 2. Traditional erosion measurement methods, such as "disassembly and weighing before and after the experiment" or "optical photography," have extremely poor measurement accuracy for the complex geometric deformation of the perforations inside the wellbore. This embodiment utilizes ultrasonic CT technology to achieve in-situ (or high-precision quasi-in-situ) scanning without damaging the experimental setup, extracting 3D change data of the diameter and volume of the perforation orifice 410.

[0085] 3. This embodiment differs significantly from existing technologies in three dimensions: "integrated physical simulation", "quantitative erosion measurement" and "active flow control". It realizes a complete experimental system that integrates dynamic distribution of multi-cluster flow, formation backpressure simulation, quantitative measurement of pore erosion and correction of theoretical models.

[0086] Example 2:

[0087] Please see Figure 1 , Figure 2 and Figure 3 This embodiment provides an erosion simulation test method, applied to the erosion test system provided in the above embodiment. It is understood that this embodiment is an improvement upon the technology of Embodiment 1 above, and the difference between Embodiment 1 and Embodiment 1 lies in:

[0088] This embodiment can obtain the erosion coefficient under different pipe materials, proppant types, and fracturing fluid types using the above-described erosion simulation test method. .

[0089] In this embodiment, the test parameters include three variable parameters: the erosion discharge rate Q1 of the formation backpressure simulation module 200, the sand concentration in the fracturing fluid, and the preset test duration.

[0090] Specifically, step S200 above: installing the fracturing wellbore 400 in the erosion testing system, setting the test parameters, and starting the test includes the following steps:

[0091] S211: Install the fracturing wellbore 400 into the erosion tooling module 100 and connect it to the fracturing device 500 through pipelines, and set three variable parameters.

[0092] S212: Deactivate the controllable flow distribution module 300 or activate it and maintain a constant flow rate. Conduct experimental tests according to the set three variable parameters and record the experimental data in real time. In this embodiment, the experimental tests are conducted by activating the controllable flow distribution module 300 and maintaining a constant flow rate, thus ensuring the accuracy and authenticity of the data. Furthermore, during the test, the pressure, density, flow rate, and sand concentration data of the fracturing fluid in the erosion channel need to be recorded in real time.

[0093] Furthermore, erosion simulation testing methods also include:

[0094] S410: Nine test schemes were designed according to the three-parameter, three-level orthogonal model. Each test scheme was set with three different variable parameters. The nine test schemes were tested in sequence. The flow coefficient of the perforation orifice 410 was determined based on the experimental data and the data after erosion in each test scheme to obtain nine data points. The erosion coefficient was determined by regression calculation based on the nine data points obtained.

[0095] Therefore, in order to obtain test data for 9 test schemes, it is necessary to repeat steps S100 to S300 until the testing of 9 test schemes is completed.

[0096] Furthermore, the diameter D of the enlarged perforation orifice 410 can be obtained in each test. p C can be calculated using the following formula (1). d , where C d The orifice flow rate coefficient is dynamically adjusted based on the erosion rate. Then, based on the obtained 9 sets of data points, the erosion coefficient under different pipe materials, proppant types, and fracturing fluid types is calculated by regression according to the following formulas (1) to (3). .

[0097] (1)

[0098] (2)

[0099] (3)

[0100] In the formula: P pf Friction resistance of the perforation hole, MPa; q i For pump displacement, m 3 / min; The density of the liquid is expressed in g / cm³. 3 N pD represents the number of holes, dimensionless; p C is the diameter of the aperture, in mm; d The orifice flow coefficient is dynamically adjusted based on the erosion rate; Q—total injection displacement, m 3 / min; t——time, s; m——total number of fracture clusters, dimensionless; —Parameters that determine the degree of pore erosion are dimensionless; —Parameters for calibrating the aperture diameter (m) 2 s) / kg; c—proppant content in fracturing fluid, kg / m 3 v — fluid velocity, m / s; —Parameters for calibrating the orifice flow coefficient, (m s) / kg; —Maximum perforation flow rate coefficient, dimensionless;

[0101] Thus, the erosion coefficient can be used through the above testing method. Import the erosion theory model to optimize the established erosion theory model.

[0102] Example 3:

[0103] Please see Figure 1 , Figure 2 and Figure 3 This embodiment provides an erosion simulation test method, applied to the erosion test system provided in the above embodiment. It is understood that this embodiment is an improvement upon the technology of Embodiment 1 above, and the difference between Embodiment 1 and Embodiment 1 lies in:

[0104] In this embodiment, the above testing method can be used to perform arbitrary single-cluster erosion testing or sequential cluster erosion testing from toe to heel.

[0105] Specifically, step S200 above: installing the fracturing wellbore 400 in the erosion testing system, setting the test parameters, and starting the test includes:

[0106] S221: Install the fracturing wellbore 400 into the erosion tooling module 100 and connect it to the fracturing device 500 through pipelines. Set the sand concentration in the fracturing fluid, the erosion discharge rate of the formation backpressure simulation module 200 as Q1, and the test time. At the same time, determine the different injection discharge rates Qn for the nth group based on the different perforation cluster positions n, where n is the cluster number from the toe to the heel. The injection discharge rate Qn = n * Q1. Also, determine the discharge rate of the controllable flow distribution module 300 as Q2, where Q2 = Qn - Q1.

[0107] S222: Based on the determined displacement Q2 of the controllable flow distribution module 300, activate the controllable flow distribution module 300 to conduct testing. During the testing process, it is necessary to record the pressure, density, flow rate, and sand concentration data of the fracturing fluid in the erosion channel in real time.

[0108] When it is necessary to complete the cluster erosion test from the toe to the heel in sequence, repeat steps S100 to S300 sequentially until the last cluster erosion test is completed, at which point the test ends. This allows us to obtain the distribution pattern of perforated sand concentration and erosion characteristics at different locations within the n clusters, providing accurate and reliable theoretical guidance for field operations.

[0109] It should be noted that, in this application, unless otherwise stated, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" used to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0110] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0111] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0112] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0113] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An erosion simulation test method characterized by, It is applied to an erosion testing system, which includes a control device, a fracturing device (500), and a horizontal wellbore fracturing cluster erosion testing device; The horizontal wellbore fracturing cluster erosion testing device includes: An erosion tooling module (100) has a fluid outlet (101). The erosion tooling module (100) is used to install a fracturing wellbore (400) to be tested. One end of the fracturing wellbore (400) is used to connect to a fracturing device (500) that provides fracturing fluid, and the other end is set through the erosion tooling module (100). An annular cavity (102) is formed between the fracturing wellbore (400) and the erosion tooling module (100). The wall of the fracturing wellbore (400) is provided with a plurality of perforations (410) facing the fluid outlet (101). A formation backpressure simulation module (200) is connected to the outlet (101) and is used to control the outlet (101) to discharge liquid at a preset constant flow rate; A controllable flow distribution module (300) is used to connect to the other end of the fracturing wellbore (400) and to adjust the bypass flow rate of the fracturing wellbore (400); The fracturing device (500) is connected to the fracturing wellbore (400) via a pipeline, and the control device is communicatively connected to the fracturing device (500) and the controllable flow distribution module (300) in the horizontal wellbore fracturing cluster erosion test device. The control device is configured to coordinate the operation of the fracturing device (500) and the controllable flow distribution module (300) based on the position of the perforation cluster simulated by the fracturing wellbore (400). The erosion simulation test method includes: Prepare the fracturing wellbore (400) to be tested and obtain the initial data of the perforation holes (410) on the fracturing wellbore (400); Install the fracturing wellbore (400) in the erosion testing system, set the test parameters and start the test. The test parameters include three variable parameters, which are the erosion discharge rate Q1 of the formation backpressure simulation module (200), the sand concentration in the fracturing fluid and the preset test duration. After the test time reaches the preset duration, the current test is stopped, the fracturing wellbore (400) is removed, and the erosion data of the perforation hole (410) is obtained; The steps of installing the fracturing wellbore (400) in the erosion testing system, setting test parameters, and starting the test include: The fracturing wellbore (400) is installed into the erosion tooling module (100) and connected to the fracturing device (500) through pipelines, and the three variable parameters are set; The displacement of the controllable flow distribution module (300) is turned off or the controllable flow distribution module (300) is turned on and the displacement is kept constant. Experimental tests are carried out according to the three set variable parameters, and experimental data are recorded in real time.

2. The erosion simulation test method according to claim 1, characterized in that, The erosion tooling module (100) is provided with a buffer tank (130) at the liquid outlet (101), and the buffer tank (130) is connected to the erosion tooling module (100); The formation backpressure simulation module (200) is located at the outlet of the buffer tank (130).

3. The erosion simulation test method according to claim 1, characterized in that, The formation backpressure simulation module (200) is a mechanical valve or a fixed nozzle; and / or, the controllable flow distribution module (300) is an electric valve, a magnetic valve or an automatic nozzle.

4. The erosion simulation test method according to any one of claims 1-3, characterized in that, The erosion tooling module (100) includes an erosion frame (110) and sealing flanges (120) disposed at both ends of the erosion frame (110). The fracturing wellbore (400) is provided to pass through the sealing flanges (120) at both ends of the erosion frame (110) and to be sealed and fitted with the corresponding sealing flanges (120).

5. The erosion simulation test method according to claim 1, characterized in that, The erosion testing system also includes a backflow recovery device (600). The liquid outlet of the formation backpressure simulation module (200) is connected to the backflow recovery device (600) through the erosion pipeline (700), and the controllable flow distribution module (300) is connected to the backflow recovery device (600) through the bypass pipeline (800).

6. The erosion simulation test method according to claim 1, characterized in that, The erosion simulation test method also includes: Nine test schemes were designed according to the orthogonal model of three parameters and three levels. Each test scheme was set with three different variable parameters. The tests of the nine test schemes were completed in sequence. The flow coefficient of the perforation hole (410) was determined according to the experimental data and the erosion data in each test scheme to obtain nine data points. The erosion coefficient was determined by regression calculation based on the nine data points obtained.

7. The erosion simulation test method according to claim 1, characterized in that, The steps of installing the fracturing wellbore (400) in the erosion testing system, setting test parameters, and starting the test include: The fracturing wellbore (400) is installed into the erosion tooling module (100) and connected to the fracturing device (500) through pipelines. The sand concentration in the fracturing fluid, the erosion discharge rate of the formation backpressure simulation module (200) is set to Q1, and the test time is set. At the same time, according to the different perforation cluster positions n, where n is the cluster number from the toe to the heel, the nth group of different injection discharge rates Qn is determined, where the injection discharge rate Qn = n * Q1. At the same time, the discharge rate of the controllable flow distribution module (300) is determined to be Q2, where Q2 = Qn - Q1. Based on the determined displacement Q2 of the controllable flow distribution module (300), the controllable flow distribution module (300) is turned on for testing.

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